Is docker good for a real time system?

What kind of app you build?Docker can not able to increase your app performance.

what does 1:1 performance even mean?

Docker is good if you want to flexibly scale up by adding containers, but its just one technique of many available

I need a 1:1 performance for my app...

If you mean that you want to extract every bit of performance that a server compute environment has, the only way you will achieve that is to have your own colocated hardware in a datacenter with no virtualization at all.

However, there are very few instances in which I would think that would be advantageous. You would get better performance and scalability by leveraging virtualization paired with horizontal scaling using either docker an elastic compute stack like AWS Beanstalk.

Or am I incorrect in the assumption of what your question is?

@gthell Docker is just a way of running an application. It is not a performance “magic bullet”.

I see docker as a personal prefference in small projects where you do not need to scale "instant".

If you want to learn and experiment test it.

Otherwise you will not gain anything using Docker.